Punch retainer for unitary cutting assembly



Feb. 25, 1969 R. 1.. WEISBECK PUNCH RETAINER FOR UNITARY CUTTING ASSEMBLY Sheet Filed Aug. 29, 1966 l Hli FIG.1

INVENTOR. RALPH L.WEISBECK ATTORNEYS Feb. 25, 1969 R. L. WEISBECK 9,

PUNCH RETAINER FOR UNITARY CUTTING ASSEMBLY Filed Aug. 29. 1966 Sheet 3 of 2 INVENTOR. RALPH L. WEISBECK Ws M ATTORNEYS Uted rates ABSTRACT OF THE DISCLOSURE A punch retainer for securing a punch against displacement from its holder, which retainer is conveniently actuatable from above the holder for movement between a punch-retaining position and a punch-releasing position without removal of the retainer from the device.

This invention relates to a punch retainer for unitary punch and die cutting assemblies of the nature generally illustrated and described in my Patent No. 3,253,493.

It has long been a problem in cutting or perforating units that often times the punch sticks in the Work piece being perforated so that the punch is not withdrawn from the work piece by the stripper springs until after the ram is withdrawn from the punch. When the punch breaks loose from the work piece, the stripper springs elevate the punch and upper plate carrying the punch with such force as to cause the punch to jump out of the bore of the holder in which it is slidably mounted.

Many types of punch retainers have been devised for securing the punch against such displacement from the holder; however, to my knowledge, none have fulfilled all of the desirable objects which I have been able to do with the present invention. Therefore, it is a prime object of this invention to provide an improved punch retainer for a unitary punch and die cutting assembly.

It is a further object of this invention to provide a punch retainer which is releasably mounted on the upper plate carrying the punch.

It is a significant object of this invention to provide a releasable punch retainer which is actuatable from a readily accessible position, preferably from above the upper plate.

It is another important object of this invention to provide a punch retainer suitable for releasing the punch while the upper plate remains on the unitary assembly.

It is another important object of this invention to provide a punch retainer suitable for quick and easy release of the punch while maintaining the upper punch plate in a normally inactive position connected with the unitary assembly such that it does not need to be removed upon removal of the punch, thereby permitting the upper plate to be mounted so as not to be displaced upon release of the punch after sticking in the work piece.

It is another important object of this invention to provide a punch retainer particularly suited for use in releasably retaining a punch on an upper plate which is suitably connected to a lower plate in a manner permitting release of the punch without removal of either of the plates relative to the unitary assembly.

Other objects and advantages of this invention will be particularly set forth in the claims and will be apparent from the following description, when taken in connection with the accompanying drawings, in which:

FIG. 1 is a fragmentary sectional view with parts broken away of the punch assembly portion mounted on an upper arm of a unitary punch and die cutting holder, such as the unitary holder shown in my heretofore referred to Patent No. 3,253,493, not illustrated in detail here since it is wellknown.

' atent 3,429,212 Patented Feb. 25, 1969 FIG. 5 is a fragmentary cross-sectional view taken along the line 55 of FIG. 4.

With reference to the figures, an upper arm 10 is the upper arm of a well-known unitary punch and die cutting holder of the nature illustrated in my Patent No. 3,253,493. Upper arm 10 is provided with an opening or bore 11 slidably receiving and guiding a punch body 12 having a flanged head portion 14 rigidly mounted at the upper end of the punch body 12, as for example, by a screw 16. The flange of the flanged punch head 14 is received in a circular milled slot 18 provided in the upper surface of an upper plate 20 and the punch body 12 and flanged head 14 are in this manner carried by the upper plate 20.

Upper plate 20 is interconnected with a lower stripper plate 22, as for example, :by a pair of flanged sleeves 24 downwardly disposed through openings 25 of upper plate 20. Sleeves 24 have smaller openings at the lower ends than the inside sidewalls thereby providing shoulders supporting heads 26 of a pair of tie bolts 28. The upper flanges of flanged sleeves 24 are received in a pair of circular milled slots 27 in the upper surface of upper plate 20 on opposite sides of milled slot 18. The sleeve ends of tie bolts 28 are threadedly received in threaded openings 30 of lower plate 22 and rigidly secured against rotational displacement by set screws 31. There are a pair of stripper springs 32 surrounding the tie bolts 28 and sleeves 24 and extending between and resiliently spacing the upper plate 20 from the lower stripper plate 2.2. A shim or spacer 33 is interposed between the upper ends of springs 32 and lower surface of upper plate 20. Stripper springs 32 are received in a pair of vertical bores 34 of upper arm 10 which are spaced on opposite sides of the punch bore 11. Lower stripper plate 22 is provided with a punch receiving bore 36 through which the punch body 12 passes prior to perforating the work piece being engaged by the lower stripper plate 22 during operation of this device, all of which is well-known type of construction. Also, in accordance with known constructions of this type, there is a lifter spring 40 between the upper arm and upper plate functioning to lift the punch (12, 14), upper plate 20, stripper plate 22 and spring units generally referred to by the numeral 35 (including sleeves 24, bolts 28, springs 32, shims 33) upwardly with less force than is exerted by the stripper springs 32, thereby to elevate the entire punch and stripper unit after the stripper springs 32 have retracted the punch body 12 from the work piece.

However, in the past whenever a construction of this nature has been provided in which the upper plate and the lower plate are interconnected, there often were punch retainers provided and upon sticking of the punch in the work piece, the punch is apt to be completely displaced from the unit as above described. If a punch retainer was provided, it was of a nature which necessitated the removal of the bolts 28 and the upper plate in order to separate the punch from the upper plate, or a punch retainer was provided directly between the upper arm 10 and the punch body 12 limiting the upward movement of the punch relative to the arm, the latter type of retainer being easily severed when the punch sticks in the work piece and is released with the terrific forces which are occasioned under such circumstances.

In order to overcome these problems I provide a punch retainer or lock element 42 of rectilinear parallelepiped or any suitable configuration slidably received in a diagonally extending slot 44 milled in the lower surface of upper plate 26. Lock element 42 extends transversely of the punch across a portion of an opening 46 (FIG. 2) which receives a lower shank portion 47 (FIG. 3) of the punch head 14. An inwardly disposed flat end surface 48 of the locking element 42 is secured in keyed relationship with a corresponding flat 50 milled in the side of the punch head shank 47. Hence, this arrangement provides a keying arrangement preventing rotation of the punch body 12 and punch head 14 about the vertical axis as well as precluding the punch from being displaced from the upper arm and plate due to the locking element overlying a shoulder 52 (FIG. 3) formed at the upper end of the punch body 12 where the fiat 50 is formed in the shank 47 of the punch head 14.

The locking element 42 is secured rigidly in the illustrated position by a locking means as for example a screw 54 extending through a hole 53 in the upper plate 20 and threadedly received in a mating threaded opening 56 provided in the locking element 42. In this manner the composite punch body 12 and punch head 14 rigidly interconnected by the screw 16 are conveniently and releasably locked in rigid relationship to the upper plate 20 and are readily releasable by actuation from above the upper plate 20 by simply unthreading the screw 54 while the upper plate is in a normally inactive position relative to the arm 10 as illustrated in FIG. 1. The spring units prevent removal of the upper plate 20 from the arm 10 while the punch is being removed unless the bolt 28 is unthreaded from the lower plate 22. When the screw 54 is unthreaded from the locking element 42, the operator may simply by finger pressure applied to the bottom of the locking element slide the locking element 42 longitudinally of the slot 44 until withdrawn from the upper plate 20 or need only slide the locking element far enough to be free of the shoulder 52 at which point the locking element 42 will simply drop into the operators hand. Thereafter, the operator simply removes the composite punch body 12 and punch head 14 and replaces the punch body or both with a like or similar unit, inserts the locking element 42 into the diagonal slot 44 until the locking element overlies shoulder 52 at the top of the punch body 12. The operator then threads the screw 54 into the locking element 42 thereby rigidly locking the locking element and in turn the composite punch body and head with the upper plate 20 ready for use under the ram of a press.

A preferred embodiment of my invention is illustrated in FIG. 4 wherein corresponding parts are illustrated by the same number followed by the sufiix A. In this embodiment, the hole 53A in the upper plate is elongated at 53B. With this construction, it is only necessary to loosen the screw 54A suffieient to permit the screw and locking element 42A to be moved to the right, as viewed in FIG. 4, until the left end of the locking element 42A is free of shoulder 52, thereby permitting withdrawal of the punch. It will be understood that as the screw 54A is unthreaded and is moved or slid laterally to the right, the head of the screw rides up the countersink 60 in the upper plate 20A. Likewise, countersink 60 locates or orients the screw and locking element in the locking position when tightened. This provides an embodiment whereby the locking element 42A never falls out of slot 44A and the screw 54A is never fully removed from the locking element.

It will be understood that other types of lifter springs are very suitable for this type of construction as, for example, the well-known type carried in a hole bored in the upper arm 20 and function to element bolts attached to the lower plate 22. However, for purposes of simplicity of the drawings, I elected to illustrate the lifter spring 40.

While I have shown and described the preferred form of mechanism of my invention, it will be apparent that various modifications and changes may be made therein,

4 I particularly in the form and relation of arts, without departing from the spirit of my invention as set forth in the appended claims.

I claim:

1. In a unitary punch and die cutting assembly having a holder with an upper arm for use between the bed and ram of a press:

(a) an upper plate mounted on said upper arm and being positioned at least partly above said arm in its normally inactive position;

(b) a punch mounted and guided on said upper arm and being upwardly removable through said upper plate;

(0) releasable punch retainer means on said plate for releasably retaining said punch on said plate and being releasably activable while said upper plate is in said normally inactive position,

(1) said releasable punch retaining means including means permitting actuation thereof between retaining and nonretaining positions without removal of said retaining means from said upper plate.

2. A unitary punch and die assembly in accordance with claim 1 including interconnecting means coactive between said upper plate and said upper arm for preventing removal of said upper plate from said holder while said punch is being removed.

3. A unitary punch and die assembly in accordance with claim 1 in which said punch has an upper flange resting on said upper plate.

4. A unitary punch and die assembly in accordance with claim 1 including a lower plate mounted below the upper arm and means tying the upper and lower plate together while said releasable punch retainer is actuated to release said punch.

5. In a unitary punch and die cutting assembly having a holder with an upper arm for use between the bed and ram of a press:

(a) an upper plate mounted above said upper arm;

(b) a punch mounted and guided on said upper arm and being upwardly removable through said upper plate;

(0) releasable punch retainer means on said plate for releasably retaining said punch on said plate and being releasably activatable while said upper plate is in a normally inactive position relative to said arm; and

(d) interconnecting means coactive between said upper plate and said upper arm for preventing removal of said upper plate from said holder while said punch is being removed, said interconnecting means including a lower plate below said arm, stripper spring means between said plates and the tie means between said plates limiting the distance therebetween.

6. In a unitary punch and die cutting assembly having a holder with an upper arm for use between the bed and ram of a press:

(a) an upper plate mounted above said upper arm;

(b) a punch mounted and guided on said upper arm and being upwardly removable through said upper plate;

(c) releasable punch retainer means on said plate for releasably retaining said punch on said plate and being releasably activatable while said upper plate is in a normally inactive position relative to said arm, said releasable punch retainer means being releasably actuatable from above said upper plate.

7. In a unitary punch and die cutting assembly having a holder with an upper arm for use between the bed and ram of a press:

(a) an upper plate mounted above said upper arm;

(b) a punch mounted and guided on said upper arm and being upwardly removable through said upper plate;

(c) releasable punch retainer means on said plate for releasably retaining said punch on said plate and being releasably activatable while said upper plate is in a normally inactive position relative to said arm, said releasable punch retainer means comprising a locking element mounted below the upper surface of said upper plate and extends substantially transversely into locking relationship with said punch and means for releasably locking said locking element in said locked relationship.

8. A unitary punch and die assembly in accordance with claim 7 in which said locking element is received in a slot in the lower surface of said upper plate.

9. A unitary punch and die assembly in accordance with claim 8 in which said punch and locking element have mating keyed surfaces.

10. A unitary punch and die assembly in accordance with claim 8 in which said punch comprises a punch head and a punch body releasably interconnected and in which said punch head and locking element have mating keyed surfaces.

11. A unitary punch and die assembly in accordance with claim 8 in which said releasable punch retainer means includes locking means extending from the upper surface of said plate to said locking element.

12. A unitary punch and die assembly in accordance with claim 11 in which said locking means includes means permitting lateral sliding of the locking element While the locking element and locking means are being carried by said upper plate.

13. A unitary punch and die assembly in accordance with claim 11 in which said locking means comprises a screw actuatable from above said assembly.

14. A unitary punch and die assembly in accordance with claim 13 in which said locking means includes an elongated slot in said upper plate permitting lateral sliding of said screw and including means for orienting said screw in the locking position.

15. In a unitary punch and die cutting assembly having a holder with an upper arm for use between the bed and ram of a press;

(a) an upper plate mounted above said upper arm;

(b) a punch having an upper flange resting on said plate and the punch body being mounted and guided on said upper arm and being upwardly removable through said upper plate;

(c) reasonable punch retainer means on said plate for releasably retaining said punch on said plate and being releasably actu'atable from above said upper plate, said retainer means including a relatively straight elongated portion adapted to move transversely into locking engagement with said punch.

16. In a unitary punch and die cutting assembly having a holder with an upper arm for use between the bed and mm of a press:

(a) an upper plate mounted above said upper arm;

(b) a punch having an upper flange resting on said plate and the punch body being mounted and guided on said upper arm and being upwardly removable through said upper plate;

(c) releasable punch retainer means on said plate for releasably retaining said punch on said plate and being releasably actuatable from above said upper plate, said releasable punch retainer means including means permitting actuation between locked and unlocked positions without removal from said upper plate.

References Cited UNITED STATES PATENTS 2,355,344 8/1944 Wales 83l40 2,622,682 12/ 1952 Kopczynski 83698 X 3,079,824 3/ 1963 Schott 83-140 3,114,280 12/1963 Schott 83l40 3,234,840 2/1966 Smeets 83559 ANDREW R. JUHASZ, Primary Examiner.

F. T. YOST, Assistant Examiner.

U.S. Cl. X.R. 83-559, 698

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3 ,429,2l2 February 25, 1969 Ralph L. Weisbeck It is certified that error appears in the above identified patent and that said Letters Patent are hereby corrected as shown below:

Column 4 line 16, "activable" should read activatable line Column 5, lines 32 and 37, "sorew" each occurrence,

53, cancel "the".

Column 6, line 6, "reasonable" should read should read screw releasable Signed and sealed this 7th day of April 1970.

(SEAL) Attest:

Edward M. Fletcher, Jr.

Commissioner of Patents Attesting Officer WILLIAM E. SCHUYLER, JR. 

